infantile [ˈɪnfənˌtaɪl, -tɪl]

例句:

• Pearl was a born outcast of the infantile world.
  珠儿生来便是那婴孩天地的弃儿.
  来自英汉文学 - 红字
• Some infantile actions survive into adulthood.
  某些婴儿期的行为一直保持到成年期.
  
• This kind of humour is infantile and boring.
  这种幽默既幼稚又无聊。
  
• What the infantile Cole tweeted yesterday was merely idiotic.
  来自THETIMES
• Infantile fears...are the precursors of many...anxieties entertained by adults
  来自E. H. Erikson
• We are all well, barring...various forms of infantile pip.
  来自T. H. Huxley